National Football League | Lyon | National Register of Historic Places | National Hockey League | England national football team | National Basketball Association | National Science Foundation | National Geographic | National Trust | National Endowment for the Arts | National Geographic Society | Argentina national football team | National Trust for Places of Historic Interest or Natural Beauty | National Park Service | National League | Australian National University | National Guard | National Geographic Channel | National Institutes of Health | National Guard of the United States | National Collegiate Athletic Association | United States National Research Council | National Portrait Gallery | National Academy of Sciences | Indian National Congress | United States men's national soccer team | National Research Council | Royal National Theatre | National Gallery of Art | Mexico national football team |
Dreyfus taught at the Schola Cantorum, at the Sorbonne in Paris, and at the National conservatory of music and dance of Lyon(CNSMD de Lyon).
In 1981 he was appointed professor of cello at the Conservatoire de Lyon.
He continued composition studies with George Benjamin (King's College London) and organ studies with Louis Robilliard (Conservatoire de Lyon, Prix de Perfectionnement), Odile Bailleux (Conservatoire de Bourg-la-Reine, Prix de Perfectionnement), and Marie-Claire Alain (regional conservatory of Paris).